I use the app on my older android phone which works flawlessly every time as the standard remote sequence was flaky and not working all the time (works on my M 6120 and no longer on my KU6000 apparently) - besides the fact that you have to power off the tv to exit while with the app you can exit and enter while the TV is powered on just like with the service remote. If you don't have a phone with IR blaster you can always build the blaster using 2 LEDs as described in the wiki, pretty straight forward.

My TV's model and my geographical area support HbbTV. But for a unknown reason samsung has this option disabled. I phoned to them and they inform me that I have to wait for few weeks for an appointment to unlock the option via online support.
If there is an option that I could change from service menu, I 'ld like to know it.
Thank you for your answer.